If you had a wallpaper changer would you be in the need for "Random time"?

So i am one the 2 devs of Wallch (Wallpaper changer for ubuntu).
As we are making version 4, we are searching for useless features that must be removed because they make things a bit more complicated..

In the mainwindow we have a checkbox asking the user to use the random time or no.

In the preferences the user can change the space of time that a random time will be created..

And i am asking, if you used a wallpaper changer would you ever use this feature? I mean everybody wants to have a stable wallapaper changing mode, so they know the wallpapers will change every 20 minutes for instance..

And at 1 of 1000 people that will use it, the other 9999 will be confused... Don't you agree?

The other dev is of the opinion that we must keep it. What do you think?